Several senior female Labour MPs declare they will not be running for deputy leader

A number of senior female Labour MPs have dropped out of contention to replace Angela Rayner as the party's deputy leader, as a compressed timetable for nominations and concerns about a toxic atmosphere narrowed the field.

- Peter Walker Pippa Crerar

Bridget Phillipson, the education secretary, is expected to enter the race, where she would be seen as a de facto Downing Street choice, potentially putting her against Emily Thornberry, who would position herself as a voice for backbenchers.

In a fast-moving process, in which hopefuls have until 5pm on Thursday to secure nominations from at least 80 Labour MPs, four women tipped as possible frontrunners have removed themselves from contention.

Shabana Mahmood said she wanted to focus on her job as home secretary, begun on Friday after Rayner's resignation as deputy prime minister and housing secretary over the underpayment of stamp duty on a second home. "My top priority is securing our borders," Mahmood told Sky News. "I will not be running for deputy leader of the Labour party."

Louise Haigh, the former transport secretary, had been expected to run as a candidate from the left. But writing in the Guardian online, she said she had decided to campaign for a new and more ambitious approach by the government from the backbenches.